One vertex per element, one color per generator, with an edge from x to x·s.
(9,10)(11,15)(12,22,24,16)(13,18)(14,17)(19,26,32,34)(20,28)(21,27)(23,35,36,29)(25,30)(31,37,39,40)(33,38)(1,2,4,5)(3,6,7,8)(9,11)(10,15)(12,19)(13,20)(14,21)(16,26)(17,27)(18,28)(22,34)(23,31)(24,32)(25,33)(29,37)(30,38)(35,40)(36,39)(2,5)(3,7)(9,12)(10,16)(11,19)(13,23)(14,24)(15,26)(17,22)(18,29)(20,31)(21,32)(25,36)(27,34)(28,37)(30,35)(33,39)(38,40) involution — undirected(1,3)(2,6)(4,7)(5,8)(10,17)(15,27)(16,22)(18,30)(26,34)(28,38)(29,35)(37,40) involution — undirected(2,5)(3,7)(9,13,14,25)(10,18,17,30)(11,20,21,33)(12,23,24,36)(15,28,27,38)(16,29,22,35)(19,31,32,39)(26,37,34,40)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.